Laser ion source

Abstract

According to one embodiment, there is provided a laser ion source. The laser ion source includes a vacuum chamber which is vacuum-exhausted and in which a target is transported and set, a valve which is opened when the target is transported into the vacuum chamber and is closed except for the transportation, a target supply chamber which holds the target to be movable, and a transportation unit which transports to the vacuum chamber the target held on the target supply chamber while opening the valve after the target supply chamber is vacuum-exhausted while closing the valve.

What is claimed is: 
     
       1. A laser ion source that irradiates a laser beam onto a target, which is transported to and set in a vacuum-exhausted vacuum chamber, the target being ionized by the laser beam, the laser ion source electrostatically extracting ions from the target to generate an ion beam, the laser ion source comprising:
 a vacuum chamber which is vacuum-exhausted and in which a target generating ions by irradiation of a laser beam is transported and set; 
 a valve which is provided on the vacuum chamber, and is opened when the target is transported into the vacuum chamber and is closed except for the transportation; 
 a target supply chamber which is attached to the vacuum chamber via the valve, holds the target to be movable, and is vacuum-exhausted independently from the vacuum chamber; and 
 a transportation unit which transports to the vacuum chamber the target held on the target supply chamber while opening the valve after the target supply chamber is vacuum-exhausted while closing the valve, 
 wherein the transportation unit is configured to transport the target along a guide rail provided between the target supply chamber and the vacuum chamber, 
 the guide rail has a cross sectional profile that corresponds to the target to engage the target so that no gap exists between the target and the guide rail in a cross-sectional view, and 
 the guide rail contacts more than one surface of the target so as to not cause a positional gap in a horizontal direction. 
 
     
     
       2. The laser ion source according to  claim 1 , wherein the guide rail is divided at the position of the valve so as not to interrupt the opening/closing of the valve. 
     
     
       3. The laser ion source according to  claim 1 , wherein the vacuum chamber includes a target shifting unit which shifts the target to change an irradiation position of the laser beam to the transported target. 
     
     
       4. The laser ion source according to  claim 3 , wherein the target shifting unit includes a fixation unit which fixes the target such that a surface of the transported target is orthogonal to a direction to generate the ion. 
     
     
       5. The laser ion source according to  claim 1 , wherein the transportation unit transports to the vacuum chamber the target held on the target supply chamber while opening the valve when the pressure of the target supply chamber is equal to or lower than the pressure of the vacuum chamber.